Demystifying the Tomato: Determinate vs Indeterminate Varieties

I suppose it’s because one can’t purchase a good tasting tomato from the grocery store, and because our pantries would be bereft without preserved tomatoes, that we place these versatile fruits so high on the “must grow” list for our home gardens.

What are the best Tomatoes to grow?

We grow tomatoes to eat fresh and to prepare a variety of recipes – which makes it obvious why, if we have the space, we choose more than one variety of tomato to grow. Most gardeners develop favorites, but in general, when choosing which variety will best fit our needs, the first thing to think about is the long-term plan for the harvest. How much space do we have? How long do we have to wait before that first ripe tomato? Are we growing for fresh eating and/or for putting away? In many cases, the answers to these questions tell us whether we want to grow a determinate or indeterminate variety.

The miracle of determinate tomatoes is that they grow on a plant on which all of the fruit ripens simultaneously – within a week or two, and they tend to ripen early. The plants are smaller and more bush like and are often a good choice for growing in containers. While all tomatoes in general like to be staked, determinates are shorter and once flowers have appeared and fruit sets, the plants stop growing and eventually die. For this reason, some gardeners skip the supports. This “miracle” could be a nightmare if what you were looking for is a tomato that is still ripening in September – but if you’d like to “put summer up in a jar”, and enjoy an early crop, these are the varieties to choose.

New Big Dwarf Determinate Tomato 

Indeterminate varieties are also called "vining" tomatoes. They grow and produce fruit until killed by frost and can reach heights of up to 10 feet although 6 feet is more normal. They will bloom, set new fruit and ripen fruit continuously throughout the growing season. They require caging and or/ staking for support and pruning off the suckering branches is practiced by many but not mandatory. Because of the need for substantial support and the size of plants, indeterminate varieties are not usually recommended as container plants. 

Mr.Stripey Indeterminate Tomato 

Some favorite Determinate varieties…

In my garden, there is almost always a couple of Principe Bourghese tomato plants because this heirloom was bred in Italy for drying. I like dried tomatoes because they are so easy to preserve, versatile, and they last forever! I collect them in batches over a week or two and toss them sliced into my home dryer overnight. Presto!

Tiny Tim is a determinate tomato specifically bred for growing in a container. The fruit is early, small, succulent and very well suited to a sunny balcony or deck right outside the kitchen. Because it fruits all at once, if you have a container garden and want the advantages of a longer season crop, try succession planting. Start some seeds 3 or 4 weeks after the first planting.

I like to freeze and can (yes, I really do like to can tomatoes and sauces) and it is so much easier to use determinate varieties like San Marzano, for its rich, delicious flavor, Rutgers for early slicing or Roma for good yield and quick sauce. Using determinates makes it easier to plan for preserving because of their simultaneous fruiting habit. Nothing, of course, stops me from eating these lovelies fresh from the garden, but mostly I count on the Indeterminate varieties for that.

If you’re looking forward to a summer long experience of fresh tomatoes, you’ll be looking for what is called an indeterminate variety – which simply means, these are vining tomatoes that continue to grow and fruit until the weather no longer permits – often, first frost. Most heirlooms and open-pollinated tomatoes are indeterminate and they come in every size, shape and color.

San Marzano Tomato  

Some favorite Indeterminate varieties…

I tend to like bi-colors like Mr. Stripey, Chocolate Stripes, and Paul Robeson for their rich taste sliced or chopped into a salad. Speckled Roman is a favorite for it’s gorgeous appearance and versatility in sauces and as a slicer. The dark tomatoes like Black Krim, Black from Tula, Cherokee Purple, make my mouth water just thinking about them and my eyes sparkle when I imagine them sliced in a sandwich or adding contrast to a sauce or salad. The huge ones like Mortgage Lifter, New Big Dwarf, or Pink Brandywine make quick work of a sandwich or sauce. You don’t need many of these to make a whole dinner. And, of course, there are all those terrific cherry tomatoes for snacking. The point is, these Indeterminates are the joy of summer until frost or disease takes them off the table.

It is worth saying that more evidence shows that pruning and staking indeterminate tomatoes helps with disease prevention and increases the size of the fruit. Stake the plants, prune the suckers, and give them plenty of space so that air can circulate. However, because of their growth habit, the more bushy, shorter determinate tomatoes should never be pruned. The suckers on determinate tomatoes, once removed will kill off the fruit and slow the yield. 

	Article Written by: Angie Lavezzo
	About the Author: Angie Lavezzo is the former general manager of Sow True Seed. Beyond her professional role at Sow True, Angie's passion for gardening extends into personal hands-on experience, fostering plants and reaping bountiful harvests.